Combined recorder and reproducer



Oct. 29, 1929. A. c. KELLER 1,733,607

COMBINED RECORDER ND REPRODUCER Filed June 30, 1928 i la BY W ATTORNEYPatented Oct. 29, 1929 1,733,607

' ARTHUR C, KELLER, 01 NEW YORK, N. Y.,

TORIES, INCORPORATED, OF NEW YORK,

ASSIGNOR TO BELL TELEPHONE LABORA- N. Y., A. CORPORATION OF YORKCOMBINED RECORDER AND REPRODUOER iv Application fllcd lane 30, 1928.Serial No. 289,515.

This invention relates in general to phonographs and more particularlyto such devices equipped for both recordingand reproduction of soundwaves with a single instrument.

In phonograph devices arranged for the recording and reproduction ofsound waves, it has long been appreciated that any lateral movement of arecording stylus should be prevented in order that a faithfulreproduction of the sound waves might be recorded on a record. On theother hand a certain amount of lateral movement should be permitted thereproducing stylus in order that it ma accuratel follow the groove ofthe recor to faith ully reproduce the sound waves without causing unduewear on the record. Various arrangements have been proposed to meetthese requirements but the resulting structures were, in general,ineflicient and so complicated as to cause difliculty in maintaining theapparatus in proper adjustment. It is, therefore, an object ofthepresent invention. to-provide an improved structure in which thereproducing stylus is allowed a certain amount of lateral motion whilethe recording stylus is prevented from any lateral movement and,furthermore, a structure which is efiicient and easily maintained inadjustment.

To accomplish this object and in accordance with a feature of theinvention, the recording stylus of a combined recorder and reproducer isrigidly secured to a pivotally mounted stylus arm to insure itsvibration in one plane only and the reproducing stylus is flexiblymounted to the stylus arm in such a manner that it is free to move in aplane perpendicular to the plane of movement of the recording stylus. na preferred embodiment this is accomplished by securing thereproducingstylus to the stylus arm by means of one or more thin metallic stripswhich are free to vibrate in a plane perpendicular to the plane ofmovement of the recording stylus but which are substantially restrainedfrom movement in the same lane.

These and other ob ects of the invention may be more clearly understoodby reference to the accompanying drawing in which:

Fig. 1 is a view of a device embodying the features of the invention andarranged for reproducing;

Fig. 2 is a view partly 'in section of the degree of Fig. 1 in theposition for recording; an

Fig. 3 is an enlarged view of the stylus arm showing its details ofconstruction.

Referring to the drawings the carriage 10 is arranged to move slowlyalong the rod 11 in the well-known'manneras the recording or re roducinstylus traces a helix on the perip cry of t e record 12, which isrotated at a suitable s eed in the direction shown by the arrow. 11electrical operating unit,

which is preferably of the general type dis-- closed in the copendingapplication of Henry C. Harrison, Serial No. 191,012, filed May I 13,1927, is enclosed in casing 13 which is plvotally mounted at 14 to thebracket members 15, which in turn, are rigidly secured to plate 16. Thisplate is arranged to slide freely through guide member 17 and isconnected by means of link 18 to the operating lever 19. Rigidly securedto the armature of the electrical operating unit is an extension mem ber21 which, in turn, is secured to the stylus arm 22 by means of asubstantially rigid rod 23. The stylus arm 22 is provided with a shaftmember 24 which rotates in suitable bearing members 25 positioned in theside bracketsi26, 27 of supporting members 28 which, in turn, is rigidlysecured to the easing 13 of the electrical unit. The stylus arm 22 isprovided near its end with a r'ecordin stylus 29 which is rigidlysecured thereto. reproducing stylus 30, as will be more clearly seen byreference to Fig. 3, is flexibly secured to the stylus arm by means offlexible strips 31, 31, these strips being preferably secured to thestylus arm by means of rivets 33, 33. The reproducing stylus 30 issecured in the mounting 34 which is riveted to the outer ends of theflexible strips 31, 31. While it is preferable to employ a plurality ofstrips 31 as shown, it is obvious that satisfactory results may beobtained by mounting the reproducing stylus at' the end of a singleflexible strip.

With the device arranged for reproducing, as shown in Fig. 1, thereproducing stylus is in engagement with the record 12 and is allowedlateral movement due to the flexure of the strips 31, 31. When in therecording position shown by Fig. 2 the recording stylus 5 is inengagement with the record 12, but since the stylus is rigidly securedto stylus arm 22,

it is not permitted any lateral movement: With the arrangement shown,due to the manner in which the device is pivoted and the relativepositions of the recording and reproducing styli', the force exertedupon the record when the device is used for reproducing is greater thanthat exerted when it is used forrecording purposes. Furthermore, 5 sincetherelative positions of the stylus arm and the electrical unit are thesame irrespective ofwhether the device is being used for recording orfor reproducing, the driving rod 23, which is positioned perpendicularto the extension member 21, provides a driving arrangement of maximumefliciency in either case.

What is claimed is: Y

1'. In a sound recording and reproducing ,2'5 device, astylus arm, arecording stylus rigidly mountedthereon, a reproducing stylus, andflexible means for joining the reproducing stylus to the stylus arm.

- 2. In a sound recording and reproducing .30 device, a stylus armarranged to vibrate in one plane only, a recording stylus rigidlysecured thereto, and a reproducing stylus flexibly secured to said armand adapted to vibrate in a plane perpendicular to the plane ofvibration of said arm.

3. In a sound recording and reproducing device, a stylus arm. arrangedto vibrate in one plane only, a recording stylus rigidlysecured thereto,a flexible member secured to 40 said stylus arm and adapted to flex in aplane perpendicular to the plane of vibration of said stylus arm, and areproducing stylus mounted at the outer end of said flexible member.

4:. In a sound recording and reproducing device, a stylus arm, arecording stylus rigidly secured thereto, a reproducing stylus and aplurality of flexible members for securing the reproducing stylus to thestylus arm.

5. In a sound recording and reproducing device a stylus arm arranged tovibrate in one plane only, a recording stylus rigidly secured to the endof said stylus arm, a plurality of flexible members fastened at one endto the stylus arm, a supporting member rigidly se-- cured to theopposite end of said flexible members, and a reproducing stylus mountedin said supporting member whereby said reproducing stylus is free tovibrate in aplane w perpendicular to the plane of vibration of saidstylus arm,

r In witness whereof, I hereunto subscribe my name this 29th day of J11118; 1928.

1 cs ARTHUR C. KELLER.

